A089835 - OEIS

A089835

a(n) = (A000108(n)^2)*(n+1)!.

1, 2, 24, 600, 23520, 1270080, 87816960, 7420533120, 742053312000, 85781362867200, 11260753452748800, 1655330757554073600, 269436914075724595200, 48113734656379392000000

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OFFSET

0,2

COMMENTS

This sequence gives the total number of non-recursive "clauses" of n opening nodes, used in the construction of A089840.

LINKS

Table of n, a(n) for n=0..13.

FORMULA

a(n) = A001246(n)*A000142(n+1) = A001813(n)*A000108(n).

PROG

(MIT/GNU Scheme) (define (A089835 n) (* (A000108 n) (A000108 n) (A000142 (1+ n))))

CROSSREFS

INVERTi transform of A089836.

Cf. A000108, A000142, A001246, A001813.

Sequence in context: A090316 A128578 A186632 * A210909 A009251 A009447

Adjacent sequences: A089832 A089833 A089834 * A089836 A089837 A089838

KEYWORD

nonn

AUTHOR

Antti Karttunen, Dec 05 2003

STATUS

approved